Obsolete — sourcing through independent channels
Diodes Incorporated lists the 1.5KE200A-T as Obsolete. No official successor is recorded.
1500 W peak pulse — what the rating means for the BOM
This is the energy the device absorbs during a transient before the clamp activates. For a 171 V reverse standoff, the 274 V maximum clamp limits the voltage seen by the downstream circuitry. The 5.5 A peak pulse current is the surge the diode shunts — a TVS selected for a 200 V nominal rail should have a standoff above the rail's maximum steady-state voltage, which this 171 V figure meets for a 170 V bus.
DO-201 axial — board-fit considerations
Through-hole DO-201AA / DO-27 axial package. The 1500 W rating assumes the leads are soldered into a PCB with adequate copper pad area for heat sinking — a free-air or point-to-point wired installation will not achieve the same pulse derating.